Kate Hudson delivered son Bingham "Bing" Hawn Bellamy on July 10. And now, eight months later, the "Something Borrowed" actress, 33, is more than ready to show off her famous bikini bod, taut and slim as it was before her second pregnancy.

In Cancun, Mexico, March 16 with Bing's dad, Hudson's fiance, Matt Bellamy of the band Muse, Hudson showed off her physique in a tiny, black-and-white-striped string bikini as she and her man lolled about in the sand and surf.

According to a source, Hudson had a dance studio built in her Los Angeles home, complete with a state-of-the-art stereo system, for daily, hourlong dance workouts. "It worked!" raves the insider of Hudson, who's also a fan of cycling. The Oscar nominee also kept to strict portions of protein and veggies, and stopped eating after 7 p.m. "She has no baby fat!" raves the friend.